MANILA (UPDATED) - Senator Antonio Trillanes IV and the lawyer of Davao City Mayor Rodrigo Duterte showed up Monday at the Bank of the Philippine Islands (BPI) Julia Vargas Branch in Pasig City, in a bid to settle the lawmaker's allegations of hidden wealth against the mayor.

Trillanes last Wednesday alleged that Duterte had P211 million in undeclared funds in his account at the BPI-Julia Vargas branch in 2014.

Duterte initially denied he had such an account but later confirmed that he had a joint account with daughter, Sara, in the BPI Julia Vargas branch.

He later agreed to open his account in a bid to debunk the Trillanes' allegation -- on the condition that the senator must present an affidavit on his allegations and identify his sources.

Atty. Sal Panelo, Duterte's lawyer, has said there is no need to disclose the entire history of the presidential bet's bank accounts to prove that he has no undeclared wealth.

No need for full disclosure of Duterte accounts: mayor's camp

Panelo reasoned that Trillanes could not have gotten the documents from a reliable source because banks are prohibited by the Bank Secrecy Law to divulge the financial records of their clients.

The lawyer arrived at the BPI-Julia Vargas branch at past 10 a.m.
He showed reporters a Special Power of Attorney requesting BPI to give a certification on Duterte's account.

Atty. Panelo shows Special Power of Attorney requesting BPI to give certification on Duterte account pic.twitter.com/yYjULL42bN | @jeffcanoy

— ABS-CBN News (@ABSCBNNews) May 2, 2016

Trillanes turned up at the bank shortly before 11 a.m.

WATCH: Sen. Trillanes arrives at BPI Julia Vargas branch. https://t.co/TrBBu8nCNL

— ABS-CBN News (@ABSCBNNews) May 2, 2016

EARLIER: Sen. Trillanes arrives at BPI Julia Vargas branch pic.twitter.com/jNZixAIfDc | via @jeffcanoy

— ABS-CBN News (@ABSCBNNews) May 2, 2016

Trillanes left BPI-Julia Vargas at around 11:30 a.m., while Panelo was still inside.

The vice-presidential bet refused to grant interviews or reveal details about the meeting.

He said he will instead hold a press conference at the Magdalo national headquarters in Quezon City later today.

SHOUTING MATCH

A shouting match ensued between the supporters of Trillanes and Duterte as they awaited developments on the controversy.

Trillanes supporters gather outside the bank; shouting match now ongoing between Duterte and Trillanes supporters pic.twitter.com/yyQaUOuc9j

— ABS-CBN News (@ABSCBNNews) May 2, 2016

Young Duterte supporters from Taguig gather outside BPI Julia Vargas branch; "Hindi sinungaling si Mayor Duterte." pic.twitter.com/s57aVfK5bS

— ABS-CBN News (@ABSCBNNews) May 2, 2016

Heated arguments between Duterte & Trillanes supporters outside the bank; Panelo &Trillanes meet inside pic.twitter.com/UxyeTCS0tB | @jeffcanoy

— ABS-CBN News (@ABSCBNNews) May 2, 2016

The followers of Duterte visibly outnumbered those of Trillanes.

WATCH: Duterte supporters now outnumber Trillanes' outside BPI-Julia Vargas branch | via @jeffcanoy pic.twitter.com/sA56jBAdeW

— ABS-CBN News (@ABSCBNNews) May 2, 2016

Police forces were deployed in anticipation of possible tension among the groups gathered outside the bank.

Mga kagawad ng anti-riot police, ipinuwesto sa harapan ng BPI-Julia Vargas branch | via @junryRP31DZMM pic.twitter.com/EkebWOJw6t

— DZMM TeleRadyo (@DZMMTeleRadyo) May 2, 2016

As of posting time, Panelo remained inside the bank premises. -- With reports from Zhander Cayabyab and Junry Hidalgo, dzMM; Jeff Canoy, ABS-CBN News